LOS ANGELES (Reuters)- The Las Vegas deputy district attorney who prosecuted Paris Hilton for cocaine possession was arrested over the weekend after allegedly buying a rock of cocaine, authorities said on Monday.

Clark County Deputy District Attorney David Schubert, 47, was taken into custody in Las Vegas on Saturday afternoon and booked on one count of cocaine possession.

Schubert, who has prosecuted Hilton and pop star Bruno Mars on similar charges, was released on Sunday after posting bail and was scheduled for an initial court appearance on Monday.

"I'm very disappointed to learn one of our prosecutors was allegedly buying rock cocaine," Clark County District Attorney David Roger told Reuters in a telephone interview. "This is an individual I placed a great deal of trust in by assigning him to a state and federal drug task force."

"That said, he was arrested and he will be charged and prosecuted like any other individual," he said. "We believe no one is above the law, including a deputy district attorney."

Roger said his office would charge Schubert and then turn the case over to Nevada's attorney general to avoid the appearance of a conflict of interest. He has been suspended pending termination.

According to an arrest report, Schubert was spotted picking up another man, identified as Raymond Streeter, while driving his white BMW in a neighborhood known for narcotics dealing.

The pair were followed to an apartment complex, where Streeter allegedly bought cocaine for Schubert. Both men were arrested after a traffic stop turned up cocaine in the car.

Streeter later told police that Schubert, who he knew as "Joe" would have him purchase $40 worth of cocaine, several times a week, according to the arrest report.

"I don't know the facts but I believe in the presumption of innocence," Chesnoff said.

Hilton, 30, was arrested last August after Las Vegas police found 0.8 grams of cocaine in her purse during a traffic stop. She was fined $2,000 and ordered to perform 200 hours of community service after pleading guilty in September.

Mars, whose real name is Peter Hernandez, was arrested for cocaine possession in September after a bathroom attendant at the Hard Rock Hotel spotted him with a bag of white powder.

The 25-year-old singer pleaded guilty in February and was ordered to serve probation, perform community service and undergo drug counseling.